/*
 * Copyright 2015-2025 the original author or authors.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package sockslib.client;

import com.google.common.base.Strings;
import sockslib.common.Credentials;
import sockslib.common.KeyStoreInfo;
import sockslib.common.SSLConfiguration;
import sockslib.common.UsernamePasswordCredentials;
import sockslib.utils.PathUtil;

import java.io.FileNotFoundException;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;

/**
 * The class <code>SocksFactory</code> represents a factory that can build {@link SocksProxy}
 * instance.
 *
 * @author Youchao Feng
 * @version 1.0
 * @since 1.0
 */
public class SocksProxyFactory {

  /**
   * Creates a {@link SocksProxy} instance with a string.<br>
   * For example:<br>
   * <ul>
   * <li>host,1080 = {@link Socks5#Socks5(String, int)}</li>
   * <li>host,1080,root,123456 = {@link Socks5#Socks5(String, int, Credentials)}</li>
   * <li>host,1080,root,123456,trustKeyStorePath,trustKeyStorePassword = Creates a
   * {@link SSLSocks5} instance</li>
   * <li>host,1080,root,123456,trustKeyStorePath,trustKeyStorePassword,keyStorePath,
   * keystorePathPassword = Creates a {@link SSLSocks5} instance which supports client
   * authentication</li>
   * </ul>
   *
   * @param value a string.
   * @return a {@link SocksProxy} instance.
   * @throws UnknownHostException  if the host is unknown.
   * @throws FileNotFoundException if file not found.
   */
  public static SocksProxy parse(String value) throws UnknownHostException, FileNotFoundException {
    SocksProxy socks = null;
    String host;
    int port;
    String username;
    String password;
    KeyStoreInfo trustKeyStoreInfo;
    KeyStoreInfo keyStoreInfo;
    SSLConfiguration configuration;

    if (value == null) {
      throw new IllegalArgumentException("Input string can't be null");
    }
    String[] values = value.split(",");
    try {
      switch (values.length) {
        case 2:
          host = values[0];
          port = Integer.parseInt(values[1]);
          return new Socks5(host, port);

        case 4:
          host = values[0];
          port = Integer.parseInt(values[1]);
          username = values[2];
          password = values[3];
          if (Strings.isNullOrEmpty(username)) {
            return new Socks5(host, port);
          } else {
            return new Socks5(host, port, new UsernamePasswordCredentials(username, password));
          }

        case 6:
          host = values[0];
          port = Integer.parseInt(values[1]);
          username = values[2];
          password = values[3];
          trustKeyStoreInfo = new KeyStoreInfo(PathUtil.getAbstractPath(values[4]), values[5]);
          configuration = new SSLConfiguration(null, trustKeyStoreInfo);
          socks = new SSLSocks5(new InetSocketAddress(host, port), configuration);
          if (!Strings.isNullOrEmpty(username)) {
            socks.setCredentials(new UsernamePasswordCredentials(username, password));
          }
          return socks;

        case 8:
          host = values[0];
          port = Integer.parseInt(values[1]);
          username = values[2];
          password = values[3];
          trustKeyStoreInfo = new KeyStoreInfo(PathUtil.getAbstractPath(values[4]), values[5]);
          keyStoreInfo = new KeyStoreInfo(PathUtil.getAbstractPath(values[6]), values[7]);
          configuration = new SSLConfiguration(keyStoreInfo, trustKeyStoreInfo);
          socks = new SSLSocks5(new InetSocketAddress(host, port), configuration);
          if (!Strings.isNullOrEmpty(username)) {
            socks.setCredentials(new UsernamePasswordCredentials(username, password));
          }
          return socks;
        default:
          throw new IllegalArgumentException("The input string should be formatted as [HOST],"
              + "[IP],[USERNAME],[PASSWORD],[TRUST_KEY_STORE],[TRUST_KEY_STORE_PASSWORD],"
              + "[KEY_STORE],[KEY_STORE_PASSWORD]");
      }
    } catch (NumberFormatException e) {
      throw new IllegalArgumentException("Port should be a number between 1 and 65535");
    }
  }
}
